Downlink dual carrier transmission is being developed in the 3rd generation partnership project (3GPP) as part of global system for mobile communications (GSM) enhanced data rates for GSM evolution (EDGE) Radio Access Network (GERAN) specifications in Release 7. With the additional capabilities of the dual carrier mobiles, the support of the new multi-slot capabilities has to be indicated by the mobile station (MS) in the Classmark 3 and MS radio access capability (RAC) as set out in 3GPP TS 24.008. As there are already quite a large number of bits in the Classmark 3 and MS RAC, increasing the size further by a large number of bits is undesirable. A large number of bits in those messages would delay the network attach procedure for the MS. However, some flexibility is needed in the MS implementation to allow early introduction of the feature in the market and this needs a number of MS classes to be allowed with varying multi-slot capabilities. Hence any new indication needs to be done in the most efficient possible way.